1. Field of the Invention
The present invention is related to panchromatic photosensitizers and dye-sensitized solar cell using the same, and more particularly to panchromatic photosensitizers and dye-sensitized solar cell using the same with better photoelectric conversion efficiency.
2. Description of the Prior Art
Petrochemical fuel contains nonrenewable energy, which will possibly run out very soon. In addition, burning petrochemical fuel results in excessive CO2 exhausts which not only pollute the air, but also become one of the primary causes of global warming. Therefore, searching for alternative energy supplies to reduce reliance on petrochemical fuels is a subject of great urgency. During the development of green energy, it is found that solar energy is the cleanest, most abundant and requires neither mining nor refinement. Solar energy, therefore, becomes the most notable field among the current development and search for new energy.
The manufacture of a dye-sensitized solar cell (DSSC) is simple and the manufacturing cost is also lower than that of a silicon-based solar cell of prior arts. Therefore, DSSC has been regarded as one of the most promising solar cell technologies following silicon-based solar cells. Because the intrinsic property of photosensitizers directly affects the photoelectric conversion efficiency of a DSSC, the photosensitizers then becomes one of key focus while conducting research on DSSCs.
A N3 dye is a photosensitizer commonly used at present, which comprises the structure shown in Formula (I). However, the absorption spectrum of N3 dye is not well matched to the solar spectrum, which makes N3 dye to respond sluggishly to solar irradiations with wavelengths greater than 600 nm, and cannot be used in this region efficiently.

Another photosensitizer of prior art is the black dye, which comprises the structure shown in Formula (II). Although black dye somewhat overcomes the drawback of N3 dye, and exhibits spectrum response up to the region of 920 nm, the process involving its synthesis is complicated, the absorption extinction coefficient in the visible region is inferior to those of the typical organic sensitizers, and not to mention of the poor synthetic yield.

To sum up the foregoing descriptions, the photoelectric conversion efficiency of a DSSC directly depends on the property of a photosensitizer; therefore, developing photosensitizers with decent photoelectric conversion efficiency is an important goal to be achieved.